Mechanisms of Quasi-Brittle Failure in Metals and Intermetallic Compounds.

Abstract

This is the final report for this program. Progress was made both on the experimental and theoretical aspects of the program. The experimental results demonstrate that single- and polycrystalline Al3Ti in the Ll2 form (by adding Fe or Cr) is intrinsically brittle; although second phase particles can make it even more brittle. The theoretical portion of the program has produced a new theory of the brittle-to-ductile transition temperature involving dislocation-screening assisted homogeneous dislocation nucleation at the transition. The model provides realistic values of the transition temperature and reduces to the well-known Rice-Thomson model at zero temperature and to the equally well-known Kosterlitz-Thouless model at zero stress.

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Document Details

Document Type
Technical Report
Publication Date
May 24, 1995
Accession Number
ADA320460

Entities

People

  • David P. Pope
  • Vaclav Vitek

Organizations

  • University of Pennsylvania

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Alloys
  • Crack Propagation
  • Crack Tips
  • Crystal Structure
  • Crystallography
  • Crystals
  • Intermetallic Compounds
  • Low Temperature
  • Materials
  • Mechanical Properties
  • Mechanics
  • Phase Transformations
  • Shear Modulus
  • Solid State Physics
  • Transition Temperature
  • Transitions
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Computational Modeling and Simulation
  • Materials Science and Engineering.
  • Powder metallurgy of Titanium alloys.